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<!-- select * from classdirector_qr_code_click_log  -->


SELECT DATE_FORMAT(create_time,'%Y-%m-%d') as `data`,count(*) FROM (
    select * from classdirector_qr_code_click_log where  create_time like  '2019-07-07%' group by student_id
) as t
group by DATE_FORMAT(create_time,'%Y-%m-%d')



EXPLAIN SELECT DATE_FORMAT(create_time,'%Y-%m-%d') as `data`,count(*) FROM (
    select * from classdirector_qr_code_click_log group by student_id
) as t
group by DATE_FORMAT(create_time,'%Y-%m-%d')



SELECT DATE_FORMAT(create_time,'%Y-%m-%d') as `data`,count(*) FROM classdirector_qr_code_click_log group by DATE_FORMAT(create_time,'%Y-%m-%d')





SELECT DATE_FORMAT(create_time,'%Y-%m-%d') as `data`,count(*) FROM classdirector_qr_code_click_log group by DATE_FORMAT(create_time,'%Y-%m-%d')



EXPLAIN select * from classdirector_qr_code_click_log where create_time >= '2019-07-06 00:00:00' and create_time <= '2019-07-06 23:59:59'





